...apocalyspe...that's pretty hard. I think it be easir if we say it's a challenge, if they can't join forces long enough to defeat the dieties or whatever then the world will end...but if they can then will everything will be fine!

rouges are cool! people will apply to be aliens...you just got to promote them more
Ex: "Oh my god! those aliens are so cool! don't you wish you were one?!"
of course you'd have to do it better than i did though....